Automatic check for elevator-doors.



A. C. PREBLB.

AUTOMATIC CHECK FOR. ELBVATOR DOORS.

APPLICATION FILED AUG. 22, 1012.

Patented July 7 THE NDRRIS PETERS CO.. PHOTO-LITHO., WASHINGTON. D. C.

rafrnnfr orrion.

ANDREW" CURTIS PREBLE, OF CHICAGO, ILLINOIS.

AUTOMATIC CHECK FR ELEVATOR-DOORS.

Specification of Letters Patent.

Patented July '7, 1914.

Application led August 22, 1912. Serial No. 716,366.

To all whom t may concern Be itknown that l, ANDREW CURTIS PREBLE, a citizen of the United States of America, and a resident of Chicago, in the county of Cook, State of illinois, have invented certain new and useful Improvements in Automatic Checks for Elevator- Doors, of which the following is a specification.

This invention relates to that class of elevator well-doors, which are made in halves connected together so as .to counter balance each other, and adapted to move simultaneously to and from each other in vertical directions in the closing and opening movements. And the present improvement has for its object to provide a simple and efficient means for automatically retarding the closing movement of the door sections, with an avoidance of noise and damage to the parts, and with which the iinal closing movement of the-sections can be easily effected, all as will hereinafter more fully appear.

In the accompanying is an elevation of a portion of an elevator door to which the present improvement is applied. Fig. 2, is an enlarged detail .ele-

vation of the present retarding mechanism,

controlling valve being shown in section. Fig. 3, is a detail vertical section of the same on line m-, Fig. 2. Fig. 4, is a detail horizontal sect-ion on line ae-, Fig. 1. Fig. 5, is a detail section of a modification.

Similar reference numerals indicate parts in the several views.

Referring to the drawings, 1 and 2 represent the respective upper and lower door sections, having movement in vertical guides 3 within the elevator well, and disposed at the sides of the doorway. As usual in the present type of well doors, the sections 1 and 2 will be connected together so as to counter balance by intermediate chains 4, which pass around overhead pulleys or sheaves 5, and are connected to lateral brackets 6 and 7 on the respective door sections, as illustrated in Fig. 1. And the connection of the chain 4to the bracket 7 of the lower door section 2 being preferably made by the usual elongated link or rod 8, for the purpose hereinafter stated.

9 is a cylinder secured vertically to the wall of the elevator well in adjacent relation to the above described rod 8. Said cylthe cylinder and like drawings: Figure 1,

vertic al inder has a lower open end, and an upper end closed by a head or cap 10, and from said upper end a passage or pipe 11 extends to the controlling valve hereinafter described.

12 is a piston moving in the bore of the cylinder 9, and having a depending piston rod 13 connected at its lower end to a crosshead 14, moving on suitable vertical guides 15, as shown. In the present construction the cross-head 14 is provided with a lateral arm 16 disposed in the path of the lateral bracket 7 of the lower door section 2, and adapted to receive positive upward movement therefrom, as said door section moves upwardly in the closing movement of the door sections.

17 is a tappet or button attached to the rod 8 aforesaid, and adapted by engagement with aforesaid lateral arm 16, to effect the descent of the aforesaid piston and its accessories, when the same fail to return by gravity.

18 is an adjustable vent valve of any usual form, disposed in the head or cap 10 of the cylinder 9, and adapted to permit a retarded fiow of air from such cylinder during the upward movement of the piston 12 in the same. The function of said valve is to prevent in a regulatable manner a rapid movement of said piston and its accessories, in the above mentioned closing movement of the door sections.

19 is the casing of the main controlling valve of the present construction, preferably disposed below the open lower end of the cylinder 9, with its passage 2O connected to the upper endof the aforesaid cylinder 9, by the passage or pipe 11 before described. And said passagealso communicates with the open air, as illustrated in Fig. 2.

21 is the movable valve member of any ordinary construction, arranged in the valve casing 19, and formed with a transverse passage 22, adapted at the proper period in the operation of the mechanism, to register the passage 2O of the valve casing and the upper end of the cylinder 9, with the open air. The valve member 21 isalso provided with a pair of operating crank ar1ns28 and 24 arranged in right-angle relation, and disposed in vertical paths separated from` each other a sufficient distance to permit independent operation of said arms by the individual means now to be described.

25 and 26 are individual tappet members l preferably secured to the piston rod 13 in arranged at the desired'vertical separation,y

and the arrangement is such that one will operate thel movable valve member 21 to open the upper end of the cylinder 9V to the open air, and `the otbe tappet member will operate said valve member to close'said upper end of the-cylinder.

4 1n the operation of the present appliance, the opening movement of the door sections isfeifected in an unimpeded manner, in that no positive operative connection prevails between the door sections and the retarding appliance during such opening movement, In the closing movement of the door sections, however, the desired retardation of the speed of the door sections is attained in the following manner: vWith the valve member 21 in the closed position'illustrated in Fig. 2, and as the lower door section 2 moves upwardly, the lateral bracket 7 carried thereon, comes in contact with the une derside of thecross-head 14, after which the twoparts move upwardly in unison, and such upward `movement of the cross-head 14, through itsattached piston rody 13, effects a compression of air in the upper portion of the cylinder 9, with the desired retardation of the parts, and the degree of such retardation is regulated as required by the adjustment of vent valve 18, heretofore described. As the piston 12 reaches a pre` determined upward travel in the cylinder 9, the lower tappet 26 carried vby the piston rod 13 of said piston, actuates the crank arm 23 of the movable valve member 21, to partially rotate said valve and bring its passage 22 in register with the passages 11 and 20 of the cylinder 9 and valve casing 19, and with the open air, to relieve the prevailing retardation, and thus permit a freeffinal closing of the door sections without sudden jar or impact and with a certainty of complete closure. f

Wfiththe described'relief from retardation just described, the piston 12 and its accessories descend by gravity, and when the same near their full downward travel, the upper tappet 25, if Vthe piston rod actuates the crank arm 24 of the movable valve member 2-1, to partially rotate the same, and move its passage 22, out of the .above described register with the passages 11 and 20, and close the same to the open air, so that the appliance will be in condition'for the next closing movement of the door sections. Should the piston 12 and its accessories fail to descend by gravity in the man` ner above stated, with the next opening movement ofthe-door sections, the tappet or button 17 on the rod 8 is adapted to engage against the top'of the lateral bracket 16v and effect the described downward movement in a positive manner.

ln the modification shown in Fig. 5, a

slide valve 21located vat theupper end of thecylinder 9, .is employed, and saidvvalve is operatively connected in the `manner shown to a pair `of crank arms 23 and 24,

and desire to secure by Letters Patent, is :-nv

' 1. 1n a retarding mechanism for counter- I balanced doors of elevator wells,the ycombination of a retarding cylinder having an outlet passage at one end, a'piston 'andpiston rod associated with said cylinderyand provided with means for intermittent operative engagement` withk a moving vpart of a counter-balanced well door, a valve disposed inthe aforesaid passage ofthe retarding cylinder, and means carried yby said/piston rod for operating said valve to cylinder of compression as the piston nears the end of its stroke in one direction, sub` stantially as set forth.

2. The'combination of a retarding cylinder provided with valve controlling said passage and having a movable valve memberprovidedvwith a 'pair of angularly disposed crank arms, a piston in said cylinder, a piston rod attachedk to said piston and having a pair ofvertically separated` tappets adapted for alternate operative engagement with aforesaid crank arms, and a cross-head carried by said piston rod and adapted forfoperativeen'gagement with va moving part anced well door, substantially as set forth. 8. The combination of a retarding cylin` der provided with a passage at one end, a

valve controlling said .passage having amovable valve member provided with a 4 pair-of angularly disposed crank arms, aA

piston in said cylinder, a piston rod-'attached to said piston and having a pair of vertically separated tappets adapted for alter-nate operative engagement with aforesaid crank arms, and a cross-head carried by said piston rod and adapted for intermit-v tent operative engagement with the inter-V mediate counterbalancing connection of a well door, substantially as set forth.

4. The combination of a retarding cylinder provided with a passage at one end, a

valve controlling said passage, a vent valve in the samek end of the cylinder, in 'said cylinder, said piston and adapted for intermittent operative connection with said controlling valve, and a cross-head carried by saidppiston, and adapted for operative engagement with a moving part of a well door, substan` tiallyas set forth. Y f

a piston relieve the Y.

of a counterbal# a piston rod attached to iso 5; The combination of a retarding cylindiate counter-balancing connection of an 10 der provided with a'passage at one end, a elevator Well door substantially as set forth. valve controlling said passage, a piston in Signed at Chicago, Illinois, this 20th day said cylinerl a piton rod attached to said of August, 1912.

5 piston an a apte for intermittent operative connection With said controlling valve, ANDREW CURTIS PREBLE' a cross-head carried by said piston rod and Witnesses: adapted for intermittent operative engage- WILLLAM A. CRoss, ment With a tappet carried by the interme- O. H. HILL.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner ot Patents, Washington, C. 

